The present invention generally pertains to video signal processing and is particularly directed to improved video signal scrambling and descrambling systems.
One technique for scrambling video signals is described in U.S. Pat. No. 4,070,693 to Shutterly. In accordance with the technique described therein, video information is scrambled by storing a video information line in a memory and then forming a scrambled video information line by retrieving the video information from the memory in a sequence different from the sequence within the line in which the information was stored. The portion at the beginning position of the stored video information line is retrieved at the last position of the scrambled video information line and the portion at the last position of the stored video information line is retrieved at the beginning position of the scrambled video information line. The respective lengths of the retrieved portions are varied from one line to the next in response to a randomly generated coded control signal.